Introduction

Remarkably, a basic breathing technique can significantly enhance your exercise tolerance and help you endure physical activity. In pursed lip breathing (PLB), one inhales through the nose and then gently exhales via pursed lips. Although those with respiratory diseases such as Chronic Obstructive Pulmonary Disease (COPD) often use PLB, athletes and fitness buffs have also found it helpful.PLB allows people to exercise longer, more comfortably, and at a higher intensity by increasing oxygen exchange and decreasing dyspnoea.

The goal of this study is to investigate how pursed lip breathing can help the body during physical activity, as well as the benefits it provides on endurance and exercise tolerance. It will also go into the physiological processes that support PLB, its benefits during exercise, and how you can implement this method into your training.

Definition of pursed lip breathing

Pursed lip breathing, or PLB, is a method to help increase the amount of ventilation and oxygen intake. This method requires a person to take a breath through the nose and let out through pursed lips slowly and deliberately. This method differs from usual breathing patterns in that it takes longer to exhale. The gentle back pressure produced by controlled exhalation, the PEEP, aids in keeping the airways open for longer. The technique is created to ensure passive contraction of the neck and shoulder muscles which occurs when the air is gradually sucked in through the nose and pushed out through the pursed lips. The positive pressure produced in the upper airways helps to decrease the bronchial narrowing and mucus plugging that occurs in the lower airways, improving lung function and respiratory effort, as well as reducing breathlessness.

What are the mechanisms of PLB to improve exercise endurance and tolerance?

Respiratory efficiency improvement 

Pursed-lip breathing has been demonstrated to increase gas exchange efficiency, lowering blood carbon dioxide levels and increasing arterial oxygen levels (SaO2). The primary cause of this effect is the encouragement of slow, deep breathing, which improves ventilation efficiency. PLB improves breathing efficiency and makes it easier to eliminate excess carbon dioxide from the bloodstream by encouraging deeper breaths and longer exhalations.

According to studies, PLB helps both healthy adults and people with lung disorders improve their oxygenation and reduce their symptoms of dyspnoea. PLB can support gas exchange and oxygen absorption in the lung by enhancing alveolar-capillary pressure differences, maximising ventilation-perfusion matching, and aiding in recruiting terminal airspaces. While we conduct any physical activity, the production of carbon dioxide is elevated, especially during aerobic exercises. PLB can reduce the carbon dioxide accumulation and allow for more effective breathing and oxygen delivery.

Enhanced exercise tolerance

Exercise tolerance refers to our capacity to sustain physical activity over an extended period of time. In some research, PLB has been shown to improve exercise tolerance by reducing fatigue, optimising oxygen delivery, and reducing dyspnoea during exertion. PLB allows users to work out for longer periods and at higher intensities before feeling fatigued.

It has been demonstrated that PLB considerably increases endurance duration, especially for people with respiratory conditions. A randomised crossover study found that using PLB during high-intensity exercise, for instance, increased oxygen saturation and endurance in patients with Chronic Obstructive Pulmonary Disease (COPD). Some patients even showed a 25% increase in exercise duration compared to normal breathing techniques.³

Similarly, in a 12-week study involving individuals with COPD, PLB was demonstrated to enhance physical function and reduce exertional dyspnoea (shortness of breath). According to results of a 6-minute walk test (6MWD), patients who participated in PLB showed significant improvements in their Borg Dyspnoea score and higher scores on the physical function scale of the Short Form 36 Health Survey.⁴ The outcomes include improved oxygen exchange and a reduction in dynamic hyperinflation (DH), a condition in which the lungs do not fully expel, leading to inefficient breathing and fatigue.

Prevention of dynamic hyperinflation

Dynamic hyperinflation (DH) is a situation of accumulation of air in the lungs, which happens when the lungs do not fully empty during exhalation. DH can cause the limitation of optimal oxygen intake and limit exercise performance, as the available amount of air decreases for the subsequent breath. Also, patients suffering from impaired lung function disease, such as Chronic Obstructive Pulmonary Disease (COPD), are more likely to be affected by dynamic hyperinflation. Those patients usually feel exhausted and out of breath when they exercise, compared with healthy adults. 

As PLB helps improve oxygen intake during subsequent breaths by lowering the amount of trapped air in the lungs, PLB might be a good choice for these patients. In other words, PLB encourages more thorough exhalation than usual, which reduces dynamic hyperinflation. PLB can help prevent DH by improving the respiratory cycle's efficiency, particularly during vigorous exercise.

What are the physiological benefits of PLB during exercise?

Respiratory efficiency improvement

PLB can help to create a controlled and efficient respiratory pattern by lowering the breathing rate. In other words, by promoting a slower expiration, PLB helps to extend the time spent for our lungs to exhale carbon dioxide, reducing the buildup of this waste product in the blood. This improves general lung function, including increasing the effectiveness of each breath in delivering oxygen and eliminating carbon dioxide. Also, this is particularly beneficial because aerobic exercise raises the production of carbon dioxide.

Increased comfort during physical exertion

The ease that PLB offers during exercise is among its most obvious advantages. The method helps people manage the physical discomfort that comes with exertion and lessen the sensation of being out of breath. PLB makes it possible to breathe more smoothly and deliberately while jogging, cycling, or strength training, which improves comfort and lessens the sense of effort.

Enhanced cardiovascular efficiency

By increasing the supply of oxygen and reducing the energy needed for breathing, PLB indirectly enhances cardiovascular function. Because the respiratory system is more efficient, the heart can work more efficiently and pump blood that is rich in oxygen to the muscles with less effort. This could eventually lead to improved cardiovascular function and health.

How to perform pursed lip breathing?

Pursed lip breathing is a simple yet very powerful method for treating dyspnea and enhancing lung health in general. Here’s a detailed guide on how to practice it:

Step 1: Begin with relaxation

Take a moment to calm your body before you begin. Release any tension you may be carrying by relaxing your shoulders. Gently place your tongue in a neutral position in your mouth while concentrating on relaxing your face and jaw. By doing this, you can lessen needless muscle tension that could be obstructing your breathing.

Step 2: Inhale slowly through your nose

Breathe deeply through your nose, taking care to inhale slowly and deliberately. As much as you can, try to fill your lungs with air, letting the diaphragm expand completely. It should take roughly two seconds.

Step 3: Purse your lips for exhalation

Your lips should be slightly pursed, like you are going to blow out a candle. This slows down the rate of exhalation by creating a tiny amount of resistance as you exhale.

Step 4: Exhale slowly and steadily

Breathe out slowly and deliberately for four to six seconds through your pursed lips. Make sure the exhalation is longer than the inhalation and try to release the air slowly and gently. This facilitates improved oxygen exchange and helps keep air from becoming trapped in the lungs.

Step 5: Repeat the cycle

Continue taking deep breaths and holding them for a long time, paying attention to keeping your rhythm constant. To control dyspnoea and enhance oxygenation, you can repeat this cycle as frequently as needed, particularly when exercising.

Who can benefit from pursed lip breathing?

PLB is advantageous for athletes, as it can improve oxygen delivery in the lungs and decrease the possibility of dyspnoea.

PLB can benefit patients with respiratory disorders, such as bronchitis, asthma, and COPD, by improving dyspnoea and lung capacity.

Older Adults usually suffer from reduced lung efficiency, and their capacity may deteriorate with age. PLB can support the preservation of exercise tolerance and lung function in older adults.

Summary

A straightforward yet effective technique for increasing tolerance to exercise and endurance is pursed lip breathing.  PLB allows us to exercise for longer periods and perform at our best by improving respiratory efficiency, decreasing dyspnoea, and optimising oxygen exchange.

The advantages of pursed lip breathing during exercise will become clear with regular practice, although it might take some time to become proficient, like any new technique. Before adding PLB to your routine, speak with a fitness trainer or a healthcare provider if you have any specific health concerns.